# WM_StartKeySharing

## C Specification

      #include <nitro/wm.h>

      WMErrCode WM_StartKeySharing(
          WMCallbackFunc    callback ,
          WMKeySetBuf*      buf );

## Description

Enables the key sharing feature

This function is only executable when the WM is in either the `MP PARENT` or `MP CHILD` state.

When the return value is `WM_ERRCODE_OPERATING`, a callback is generated after the key sharing feature is enabled.

After the key sharing feature is enabled, you can communicate using MP communications-based key sharing.

## Arguments

`callback` | Callback function to call when an asynchronous process completes.
`buf` | Pointer to the buffer that stores key information. Because the ARM7 processor writes directly to the buffer, be careful of coherency with the cache.

## Return Values

Returns the process result as a `WMErrCode` enumerated type.

## See Also

`WM_EndKeySharing`, `WM_GetKeySet`

## Revision History

10/22/2004 Changed return value type
08/02/2004 Standardized structure names
07/29/2004 Added descriptions
07/23/2004 Initial Version